Live firefighter training exercises typically involve the use of a training tower or other training structure specially designed for the purpose of training firefighters. These structures generally include two or more rooms. Simple training structures, for example, may have only two rooms. One of the rooms is typically designed to accommodate the fire used in live firefighter training. The other room is provided for the purpose of allowing firefighters to enter the structure to put out the live training fire. Other more sophisticated training structures may have several rooms and several floors, including two or more rooms that are specially designed to contain live training fires.
Firefighter training structures are typically made from either concrete or steel. These materials are susceptible to damage from high heat and high temperatures. When concrete is heated to a surface temperature of 650 degrees Fahrenheit, for example, it begins to lose its inherent moisture and at 750 to 850 degrees, the surface begins to powder leading to continued deterioration. Hot rolled steel will distort at 1000 degrees Fahrenheit and cold rolled steel can fail at temperatures as low as 800 degrees Fahrenheit. The structural framework and components of training structures made from these materials, therefore, must be protected from exposure to the intense heat that can be generated by a live training fire.
The room (or rooms) in a training structure that actual contains the live training fire is referred to as the burn room or live fire burn room. Burn rooms can withstand continuous exposure to intense heat from live training fires without sustaining damage because of their special design. For example, some burn rooms can withstand continuous internal temperatures of greater than 1000 degrees Fahrenheit inside of the burn room during an entire firefighter training exercise without sustaining damage. Other burn rooms have the capability of withstanding continuous temperatures up to and including 1200 degrees Fahrenheit inside of the burn room throughout an entire firefighter training exercise without sustaining damage. Some other burn rooms can even withstand continuous temperatures of greater than 1200 degrees Fahrenheit inside of the burn room throughout an entire firefighter training exercise without sustaining damage.
Many burn rooms are also designed to keep the intense heat generated by live training fires inside of the burn room. This is usually accomplished by insulating both the walls and the ceiling of the burn room. As previously discussed, it is desirable to keep the heat from live training fires inside of the burn room to protect the structural integrity of both the burn room and the remainder of the training structure.
The walls and ceiling of prior art live fire burn rooms, like the other structural components of firefighter training structures, have typically been made of concrete or rolled steel. In one type of prior art concrete burn room, for example, the walls and ceiling of the burn room are made from concrete or concrete block. The inside surfaces of the concrete or concrete block walls and ceiling are lined with special refractory concrete or refractory tiles. The refractory concrete or tiles protect the concrete walls and ceiling from damage that would otherwise result from the heat generated inside of the burn room by the live training fire.
The problem with refractory concrete or refractory tiles is that these materials do not provide good insulation. As a result, the heat generated inside of the burn room by live training fires has a propensity to escape out of the burn room and into the remainder of the training structure. In addition, refractory concrete and tiles are subject to damage from impact with foreign objects and these materials are expensive to replace.
Other prior art burn rooms have walls and a ceiling that are constructed using conventional framing members. These prior art burn rooms, for example, have walls and ceilings that are framed in using wall studs and ceiling joists made from either metal or wood. The wall studs and ceiling joists are covered with special insulating panels that protect these structural components from the heat generated inside of the burn room. These insulating panels also provide adequate insulation to keep the heat generated by the training fire inside of the burn room and away from the structural components of the burn room and the remainder of the training structure.
FIG. 1 shows the construction of a prior art burn room wall 100 having a conventional steel framework as discussed above. The structural framework of wall 100 is comprised of a plurality of equally spaced apart, vertically oriented, framing members or wall studs 102. Attached to wall studs 102 are a plurality of horizontally oriented steel hat channel members 104. Hat channel members 104 are perpendicularly attached to wall studs 102 and are equally spaced apart between the top and bottom of wall 100.
A plurality of insulating panels 106 are mounted to hat channel members 104. The insulating panels are typically 4 feet by 4 feet in size and are typically 1 inch thick. Insulating panels 106 are mounted to hat channel members 104 using conventional metal mounting screws 108 and plate washers 110. Screws 108 are typically inserted into holes 112 that are drilled completely through insulating panels 106. Thus, each mounting screw 108 penetrates from the inside of the burn room completely through an insulating panel 106 and into a metal hat channel 104 in this prior art system.
The diameter of each hole 112 is typically larger than the diameter of screws 108. For example, the diameter of each hole 112 may be on the order of ½ inch in diameter while the diameter of each screw 108 may only be ⅛ inch. The reason for providing oversized mounting holes is to allow for movement and slippage of the individual insulating panels 106 as they expand and contract with increases and decreases of temperature inside of the burn room.
Each panel 106 is mounted side-by side next to an adjacent panel, 106. Small gaps 114 are provided between adjacent panels 106 to further allow for expansion of the panels as the temperature in the burn room rises during usage. To prevent heat from escaping through gaps 114, narrow insulating batten strips 116 are mounted to hat channels 104 behind each gap 114. Hat channel spacers 118 are also provided at the center of each panel to account for the thickness of the insulating batten strips 116 that are disposed around the perimeter of each panel 106.
Insulating panels 106 and insulating battens 116 are generally made from calcium silicate boards that have been specially treated to protect them from water damage that would otherwise result from the water used during firefighter training exercises. Insulating panels pre-cut to the 4 foot by 4 foot by 1 inch size are sold by the present assignee of this application under the brand name Westemp®. Insulating panels in other sizes are also readily available. Batten strips 116 are generally pre-cut to the desired size at the factory prior to installation.
Although the prior art insulating system shown in FIG. 1 generally provides for adequate insulation to protect the structural framework and components of the burn room and training structure, it too suffers from several drawbacks. To begin with, the individual insulating panels 106 are expensive to replace. This is important because, in general, they have a limited useful life after which time they must be replaced. The panels are also susceptible to damage from impacts with foreign objects and to premature spalling and/or cracking that can result from various environmental conditions present in the burn room during firefighter training exercises (e.g., various heat/moisture conditions). Damaged panels as well as panels that show signs of significant cracking and/or spalling may also require replacement.
Proper installation of insulating panels 106 is also difficult to achieve. This is because as the panels heat up, they have a tendency to move and slip due to warpage and expansion. To allow for this movement, mounting screws 108 must be adjusted properly. If mounting screws 108 are over tightened, the insulating panels will crack at the location of the mounting screws because they will not have the ability to expand and move properly at those locations.
To further complicate matters, the greater the rise in temperature, the greater the expansion and warpage that results. What may be an adequate adjustment of mounting screws 108 at one temperature may not allow for adequate expansion and movement of the insulating panels at a higher temperature. Furthermore, if the screws are left too loose, the panels will not be properly secured to the walls when the burn room is at lower temperatures such as normal room temperature. Excessive warranty costs can be incurred to replace insulating panels that are damaged as a result of improper installation.
Another problem with the prior art insulating system of FIG. 1 is that the insulating system does not provide a complete thermal block between the inside of the burn room and the metal structural framework of the burn room. This is because the metal mounting screws that secure the insulating panels in place penetrate completely through those insulating panels. Thus, the metal mounting screws breach the layer of insulation that is provided to insulate the inside of burn room from the structural framework of the burn room.
It is desirable, therefore to have a live fire burn room that does not suffer from the drawbacks present with the prior art systems. Preferably, the live fire burn room will have an insulating system for which proper installation is easily achieved. The insulating system will also preferably have an unlimited useful life and will not be subject to damage from impacts with foreign objects or from environmental factors. Finally, the insulating system will also preferably provide a complete thermal block wherein none of the insulating system mounting components will penetrate through the insulation layer that is provided to shield the burn room from the remainder of the training structure.